1. Field of the Invention
The present invention is directed generally to a method and apparatus for simulating the paying out of elongate, flexible communication lines from a rocket or missile or other aircraft being launched and flown.
2. Description of Related Art
Many recent weapon and surveillance systems utilize elongate, flexible communication lines in ground to air communication and air to air communication, i.e., between a rocket, missile or aircraft and a ground station or another aircraft. The elongate, flexible communication lines usually comprise wire or optical fibers. Typically, the wire or optical fiber communication lines are uniformly folded or stored on a spool inside the rocket, missile or aircraft and are payed out during take off and flight. The wires or optical fibers are, therefore, frequently subject to high levels of stress from sudden and rapid accelerations and from multiple Mach level payout velocities. The dynamics, mechanics and performance as well as the physical integrity and reliability of the wires or optical fibers are therefore critical for communication with and proper control and operation of the missiles, rockets and aircraft. Thus, a method of simulating the payout of wires or optical fibers in long lengths in a controlled environment where the dynamics, mechanics and performance as well as the physical integrity and reliability of the wires or optical fibers may be experimented with, studied and reliably demonstrated and tested in a cost effective manner was needed.
As a general proposition and from a logistical standpoint, it is difficult to study the payout dynamics, mechanics and performance of wires or optical fibers. It is hardly practical and cost effective to study, measure or conduct experimentation of payout characteristics and patterns of wires or optical fibers during actual launch and flight of missiles, rockets or aircraft. The cost of conducting enough demonstrations and experimentations on particular wires or optical fiber using actual flights to obtain statistically reliable and meaningful data and results would be prohibitively expensive. Furthermore, the technical requirements of such experimentation and demonstration would present a severe logistical burden.
There are several basic guidelines, criteria and preferences for effectively simulating the paying out of wire or optical fiber communication lines from a missile, rocket or aircraft: the payout simulation must be conducted using long lengths of communication lines; the means used for payout simulation must not themselves damage the communication lines in order to properly attribute a cause of damage or distortion of the lines to a payout factor and, also, so that the expensive communication lines may be reused; the payout acceleration and the final payout velocity must accurately reflect the acceleration and velocity during actual missile, rocket or aircraft launch and flight; and the rate of simulated payout acceleration and payout velocity should be controllable and variable.
Early attempts at payout simulation comprised a bow and arrow arrangement whereby the communication line was attached to an arrow and launched from the bow. Although this method illustrates the concept of testing the payout of communication lines, it is wholly unsatisfactory since the acceleration, velocity and range are insufficient and without uniform, accurate and reliable control to provide any meaningful and reliable data and results.
Another method of simulation comprised attachment of a communication line to a rocket sled which was ground fired along a rail. Although this method may have closely simulated the actual aerial launch of a missile or rocket, it was unsatisfactory since the communication line was damaged by contact with the ground and/or the rocket plume. Further, reliable measurement of performance and collection of accurate and meaningful data were not possible due to the short survival period of the communication line due to ground contact and the harsh rocket plume environment. Additionally, the dangerous nature of these tests and experiments dictated that the test sites be confined to remote, desert test sites. Furthermore, the cost of using this method could be hardly less expensive, if not actually more, than using actual aerial missile launches.
Finally, a feeding machine was developed for use in a laboratory environment. In using a feeding machine, the communication line is fed between two high speed pinch rollers in much the same way magnetic tape is fed between pinch rollers in a cassette deck. The feeding machine, however, suffers from several drawbacks. Due to the high peripheral velocity of the pinch rollers, the rollers must be constructed of high strength, light weight metal. The metal rollers cause slippage of the communication line during feeding operations resulting in non-uniform feed rates and unpredictable results. The metal rollers also wear rapidly and also cause rapid wear and damage to the wire or optical fiber. Good control of wire or optical fiber acceleration and velocity with reliably meaningful data and results are therefore difficult to obtain if not impossible to obtain using the pinch roller feeding machine.
Additionally, pinch roller feed machines require close contact by the operator during operation since the wire or optical fiber are manually fed between the spaced rotating rollers. In order to initially begin feeding, manual reduction of the space between the rollers while manually holding the wire or optical fiber between the rollers is necessary until the wire or optical fiber is gripped between the pinch rollers. The chances of limb and life threatening accidents are high due, especially, to the possibility of accidental impact between the rollers which could cause overstress of the rollers resulting in flywheel-like disintegration and due to the possibility of the operator being gripped by the pinch rollers. Another disadvantage of pinch roller feed machines is that there is no method of collecting the wires or optical fibers after they are fed through the machine, and consequently, the wires or optical fibers after exit from the machine are not only non-reusable but also become a hazard for the laboratory environment.
The present invention overcomes the problems and disadvantages of the prior art by providing a novel method and apparatus for simulating the payout of elongate, flexible communication lines. The present invention represents a vast improvement and a completely novel approach for satisfying and meeting the needs, requirements and criteria for effective and useful payout simulation in a safe and cost effective manner.
Additional objects and advantages of the present invention will be set forth, in part, in the description which follows and, in part, will be obvious from the description or may be learned by practice of the invention. The objects and advantages of the invention may be learned by and attained by means of the instrumentalities and combination of steps particularly pointed out in the appending claims.